... Many bright nebulae and star clusters in planet Earth's sky are associated with the name of astronomer Charles Messier, from his famous 18th century catalog. ... NGC 6903: The Butterfly Nebula . ... The Nebula's glowing gas surrounds hot young stars at the edge of an immense interstellar molecular cloud. Curiosity: Wheels on Mars . ... The Eagle Nebula and the Swan Nebula span this broad starscape, a telescopic view of the Sagittarius spiral arm toward the center of our Milky Way galaxy. ...

... 2004 May 5 . NGC 6302: Big, Bright, Bug Nebula . ... ESA , NASA . Explanation: The bright clusters and nebulae of planet Earth's night sky are often named for flowers or insects , and NGC 6302 is no exception. With an estimated surface temperature of about 250,000 degrees C, the central star of this particular planetary nebula is exceptionally hot though -- shining brightly in ultraviolet light but hidden from direct view by a dense torus of dust. ... About APOD | ...

... Armagh Planetarium . ... Universe . ... Posted on October 1, 2010 | ... Before the modern era of technological astronomy, to know anything [ ] . Continue Reading.. ... 2 Comments In, say 1975, there was only one kind of ?stuff? in the Universe, matter made of protons and neutrons. ... Newer Entries . Hello, IтАЩm Colin, welcoming you to Astronotes, the PlanetariumтАЩs official blog. Here you will find the latest news and views from the fascinating worlds of astronomy and space exploration. ...

... Tonight's Sky . ... The Magazine . ... Observing . ... The double star 54 Leonis, spiral galaxy NGC 3198, and emission nebula NGC 3199 . ... Astronomy for Kids . ... Observing springtime deep-sky objects with a large telescope . ... Bright planets meet at dusk . ... Astronomy magazine subscribers can read the full article for free. ... Get instant access to subscriber content on Astronomy.com! ... Receive news, sky-event information, observing tips, and more from Astronomy's weekly email newsletter....

... 2000 August 4 . M15: Dense Globular Star Cluster . ... In fact, only 40,000 light-years away in the constellation Pegasus, M15 is one of the most densely packed globular star clusters in our Milky Way Galaxy. This stunning Hubble Space Telescope image of M15 shows thousands of individual stars across the central 10 or so light-years of the cluster, also cataloged as NGC 7078. ... Globular star clusters harbor from a hundred thousand up to a million stars and roam the Milky Way halo. ...

... The Pleiades star cluster, also known as the Seven Sisters and Messier 45, is a conspicuous object in the night sky with a prominent place in ancient mythology . ... The stars in the Pleiades are thought to have formed together around 100 million years ago, making them 1/50th the age of our sun, and they lie some 130 parsecs (425 light years ) away. ... Data for these stars are listed in a table below. ... Yes . ... WEBDA Pleiades cluster data . ... M45: The Pleiades Star Cluster (2007 November 18) ...

... Conjunction Over Armagh . ... Comet and Pleiades . ... Pleiades . ... Antares Region . Helix and Cat's Eye Nebulae . Orion Nebula . Lagoon and Eagle Nebulae . Crab Nebula . ... Our Galaxy Core . Andromeda Galaxy . Wide-field and Zoomed-in Galaxies . Interacting Typhoons and Galaxies . Spiral Galaxy M106 . Sombrero Galaxy . Whirlpool Galaxy . Colliding Galaxies . ... й Miruna Popescu, Armagh Observatory ...

Photon Scattering: Basic Principle of Photon Scattering . Audio Narration is available . No Scattering: Photon Source and Detector . ... For optical photons, scattering goes as wavelength to the -4 power. In the case of blue photons compared to red photons, this means that blue photons are about 10 times more likely to get scattered than red photons. ... Watch the blue photons scatter away from the detector . ... Interstellar dust make stars appear redder than they really are . ...

... We still have a long distance to cover before we leave the Milky Way Galaxy -- tens of thousands of lightyears, as a matter of fact -- so let's stop by some interesting objects on the way. ... But we have reached the edge of the Milky Way Galaxy. ... We don't know, but we do know that there are countless voyages left to take. To continue the virtual voyage beyond our galaxy, go to Kent Cheatham's "A Walk in the Stars" at http://www.ionet.net/~cheatham/astro/astrotour.shtml . ...

GALAXIES cenA .tiff 40 Bright Radio Galaxy M31.tiff Nikon Andromeda Galaxy (note HII regions in spiral arms) ngc6744.tiff 40 NGC 6744 a face-on spiral clouds_20d.tiff H'blad The Magellanic Clouds our nearest neighbours Lmc_7.tiff Nikon The Large Magellanic Clouds Lmc_zoom.tiff Nikon Detail of previous image smc_7.tiff Nikon The Small Magellanic Clouds smc-zoom.tiff Nikon Detail of previous image 30dor_40_BVR.tiff 40 The 30 Dor ... B [OIII] Halpha trifid.tiff 40" The Trifid Nebula. ...

... Abstract . ... Dean Hines, Space Science Institute . Imaging Scattered Light from Debris Disks Discovered by the Spitzer Space Telescope Around 20 Sun-like Stars . ... Massimo Robberto, Space Telescope Science Institute . ... Bill Sparks, Space Telescope Science Institute . ... Thomas Puzia, Space Telescope Science Institute . ... Keith Noll, Space Telescope Science Institute . ... Adam Riess, Space Telescope Science Institute . ... Tom Brown, Space Telescope Science Institute . ... Past weeks: . ...

... Bad Astronomy . ... Bitesize Astronomy . ... The next step up are true clust